Frank Gore Is Fighting for His Job—Literally

During the NFL off-season, San Francisco 49ers workhorse running back Frank Gore has been honing his conditioning with boxing.

Frank Gore has been known to deliver the knockout punch on a weary defense to close out a victory for his San Francisco 49ers. Turns out, the heavyweight in the 49ers' backfield has been honing his boxing skills during the last three NFL off-seasons.

Ryan Maquinana of has the details on Gore's off-season boxing program at the Undisputed Boxing Gym in San Carlos, California:

"As for the training regimen, it resembles the one [owner Brian] Schwartz and associate Mike Bazzel drew up for current featherweight champion Nonito Donaire, and Gore, coming off his third straight Pro Bowl season, swears by it.

"When I see a guy on the football field huffing and puffing, I know I got an advantage over him," the 31-year-old reveals after punching Schwartz's focus mitts for 30 consecutive minutes without rest. "Since I started boxing, between plays (on the football field), I'm standing straight up."

As Maquinana notes, "In a league where running backs on the wrong side of 30 are advised to preserve their bodies, Gore is pushing his to the brink."

A 31-year-old running back who's logged more than 2,000 career carries, Gore shows no signs of slowing down. "Frank the Tank" hasn't missed a game since 2010, and his nine touchdowns last season were the second-highest of his career.

However, the 49ers' all-time leading rusher must fight to keep his starting job as he enters his 10th NFL season.

The 49ers enter camp with a crowded backfield, having added former Ohio State workhorse Carlos Hyde in the second round of the 2014 NFL Draft. Marcus Lattimore will make his NFL debut after spending last season rehabbing from a knee injury. Holdovers Kendall Hunter and LaMichael James will also factor into the mix.

RELATED: Watch Video of Carlos Hyde's Pre-Draft Workout

Gore is also a regular at Bommarito Performance Systems in Miami, where fellow 49ers Colin Kaepernick and Vernon Davis set up shop in the off-season.

RELATED: Check out Maurice Jones-Drew's Off-Season Workout at Bommarito

Gore says, "The only thing I can do right now is keep getting in shape … and when the season starts, go play football and try to be the Frank Gore that I've always been."

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